At present, there are electronic devices including information processing apparatuses such as tablet and convertible notebook computers (laptop computers) and portable information terminals. Out of these, there are electronic devices that are designed to be able to change the display orientations of their display screens according to the orientations of the own electronic devices. These electronic devices are known for a function of changing the display orientation of a display screen according to user operation.
In order to detect the orientation of an electronic device, the electronic device is equipped with a sensor such as an accelerometer sensor or gyro sensor, which detects the direction of gravity and the direction of operation. This sensor enables the electronic device to automatically adjust the display orientation of the display screen when rotated by a user. Therefore, the user is always able to view the display screen and operate the electronic device in a proper orientation.
Further, there are electronic devices that provide a plurality of thresholds for determining whether to change a display orientation. By selecting appropriate thresholds, the user is able to have desired setting for change of the display orientation. There are also electronic devices that detect the tilts of the own electronic devices on the basis of a history of tilts detected by a tilt sensor so as not to react to some shakes and movements made in a short time.
Please refer to Japanese Unexamined Patent Application Publications Nos. 2009-49512 and 2004-219791.
However, it is troublesome for a user to change settings by manually selecting thresholds depending on situation.